/*
 * ICGenerator.h - Declaration of the ICGenerator class
 *
 * Part of the assignment of the Compiler Construction course
 * LIACS, Leiden University
 */

#ifndef _ICGENERATOR_H_
#define _ICGENERATOR_H_

#include "debug.h"
#include "SyntaxTree.h"
#include "SymbolTable.h"
#include "types.h"
#include "IntermediateCode.h"
#include "IOperand.h"


// This class handles the intermediate code generation. Extend it to your own
// needs.
class ICGenerator {
  public:
    // Constructor
    ICGenerator();

    // Destructor
    ~ICGenerator();

    // Preprocesses the syntax tree; this method is called before
    // GenerateIntermediateCode() if optimizations are enabled
    void Preprocess (SyntaxTree * tree, SymbolTable * symtab);

    // Takes a SyntaxTree and converts it into an IntermediateCode structure
    IntermediateCode * GenerateIntermediateCode (SyntaxTree * inputTree, SymbolTable * symtab);

    // Postprocesses the intermediate code; this method is called after
    // GenerateIntermediateCode() if optimizations are enabled
    void Postprocess (IntermediateCode * code, SymbolTable * symtab);

  private:
    // Generates a temporary symbol
    Symbol * GenerateTempVar(ReturnType type);

    // Generates a Symbol for a label
    Symbol * GenerateLabel();

    // Goes recursively through the syntax tree while appending intermediate code
    // Returns a new IOperand, allocated on the heap, with the result of the subtree
    // or returns NULL if there is no operand
    // dest is an optional destination operand, if used returns dest
    // constant is an optional constant operand
    // dest and constant are always NULL if not optimizing
    IOperand * Treewalk (Node * node, IOperand *dest = NULL, IOperand *constant = NULL);

    // Generates code for the NODE_RELOP_* nodes.
    // op is one of the IOP_B??_? operators and node is the relop node.
    // Returns a new copy of the result operand.
    IOperand * GenerateRelopCode(IOperator op, Node *node);

    // returns true if operand is a constant zero
    bool IsZero(IOperand *operand) const;
    // returns true if operand is a constant one
    bool IsOne(IOperand *operand) const;
    // returns true if operand is a constant negative one
    bool IsMinusOne(IOperand *operand) const;
    // returns true if operand is a constant
    bool IsConstant(IOperand *operand) const;
    // returns true if operand is a constant integer
    bool IsInt(IOperand *operand) const;
    // returns true if operand is a constant real
    bool IsReal(IOperand *operand) const;
};

#endif